An orthogonal frequency division multiplexing (OFDM) channel is composed of many subcarriers of a fixed bandwidth. Each subcarrier may use a different modulation. With the introduction of OFDM technology to communication channels in a cable network, it is desirable for cable modems receiving data downstream over a downstream communication channel to be informed of the modulation used by each of the subcarriers. An informed cable modem can use a particular modulation to receive downstream communications on the desired subcarrier in the spectrum of the OFDM channel. Thus, techniques for informing a cable modem of the modulation used by subcarriers in an OFDM channel are desirable.
It is noted that while the accompanying FIGs. serve to illustrate embodiments of concepts that include the claimed invention, and explain various principles and advantages of those embodiments, the claimed invention is not limited to the concepts displayed, as additional embodiments would be readily apparent to those of ordinary skill in the art having the benefit of the description herein such that a display of certain concepts are not necessary to understand such embodiments.